2001 blazer won't start

[twister4000]

Please help!!!Daughter drives daily,and two days ago it wouldn't start.It sat for about an hour,till i got off work.I tried starting it and it fired right up.Took it to an Auto Zone for a code read. Reader said there was an error,and wouldn't give a code.Ask associate to pull a battery test.He did and it said to charge battery and re test.We did and test showed battery to be at12.45.The next day Blazer wouldn't start.Sprayed starting fluid in the throttle body,it started and ran for a few seconds and died again.It still will not start. Going to replace fuel filter tomorrow.I believe it to be the origional factory filter.Are there any special tools needed to disconnect the clamp at the back side of the filter.Open box end wrenches for the forward end.If this does not fix the problem where do i look next.Any helpful information will be greatly appreciated.

[rhandwor]

http://www.autopart.com/tools/toolsmain/tool/T_A396.htm
http://www.autopart.com/tools/toolsmain/tool/T_A859.htm
These are two handy tools to have. Some you pinch the two plastic tabs on the back and pull. If original equipment it may have 4 tabs try using a hose clamp around them to compress all four at the same time. The wrench maybe needed if its corroded sometimes an open end won't work.

[ronaldk]

in your post you say you sprayed starting fluid in TB and it ran then died. that shows its running on start fluid . Thinking you are not getting fuel !! check pressure at rail and if someone can turn key on listen at gas tank for fuel pump if you dont hear check fuel pump circuit, like relay and grounds at tank also if batt bad or poor connections can cause bad charge and a low batt can cause all kinds of problems with vehs that need brain to function.The reason I dont think filter, is your statement it sat then fired right up and you drove to autozone. Not saying bad idea to change filter although you say its orig you dont give miles. Its not likely if filter was that restricted that you would make any trips but I have seen intermitent fuel pumps,relays and grounds its still not a bad idea to change but I always think the worst so I dont get caught off guard.Good luck

[skyzend]

A couple of pointers ...

I think fuel filter is a good start. Fuel pressure may be near the minimum to sustain the injectors firing. What can happen is that a clogged filter cannot sustain the fuel flow needed to meet the minimum fuel pressure for injectors to fire. The initial key turn will start the pump to build up pressure which may cause the engine to fire momentarily until the pressure disapates and then you are done. You definately need a fuel pressure guage to monitor this. Without it you will be just making assumptions and no nearer the solution. If its the original then change it anyway. I've heard that clogged filters can cause down the roud fuel pump failures ... very costly replacement.

Some other things to consider ... was it damp out when it wouldn't start ... this may indicate old plug wiring that needs replacement. I found this to be the case with my 1999. Bad wiring can lead to arcing and zero spark plug action ... I have a thread on my experience with this. Similar symptoms to yours.

Lastly ... when it won't start have a look and see if the security light is flashing. If it is, I'd bet that your ignition switch needs replacing. The passlock system detects something wrong with your key and disables the car for 10 minutes. A worn ignition switch can start to throw a security error from time to time. This problem will start off intermittantly sometimes and then progressively get worse leaving you stranded at the worst possible time. By the way this security error will not be stored and will not show up as an error code. Seems like your symtoms show up nicely in this scenario ... check the security light.

The fact you sprayed engine starter into the intake and it momentarily started does not discount the passlock error. When the passlock error is encountered, the ignition is not turned off. the engine will run if it has fuel. The passlock when in security mode effectlivly disables the injectors.

I've seen a weak battery (not at full charge) not be able to provide enough ignition voltage to overcompensate for crappy ignition wires.

Bottom line is that you have provided some good symptoms that need further investigation. Intermittant problems are tricky ... the key is to NOT ignore any of the symptoms and jump to a cause. You may have 2 problems here that just compound each other.